Correction:The escape mechanisms of the proto-atmosphere on terrestrial planets:“boil-off”escape,hydrodynamic escape and impact erosion

In the original publication of the article,the affiliation“College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing,People’s Republic of China”for author Ziqi Wang was missing and included in this correction article.

Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf:TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS

We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 B.Exoplanet candidates provided by the Transiting Exoplanet Survey Satellite(TESS)are suitable for further follow-up observations by ground-based telescopes with small and medium apertures.The analysis is performed based on data from several telescopes worldwide,including telescopes in the Sino-German multiband photometric campaign,which aimed at confirming TESS Objects of Interest(TOIs)using ground-based small-aperture and medium-aperture telescopes,especially for long-period targets.TOI-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric data.We measure an orbital period of 2.310644±0.000001 days,the radius is 0.767+0.045-0.041RJ and the amplitude of the RV curve is 69.4_(-7.3)^(+7.9)m s^(-1).TOI-1251 B is confirmed based on the multiband photometric and high-resolution spectroscopic data,whose orbital period is 5.963054+0.000002-0.000001days,radius is 0.947+0.035-0.033 R_(J) and amplitude of the RV curve is 9849_(-40)^(+42)ms^(-1).

Black Hole Singularities and Planetary Formation

The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift observations from the James Webb Space Telescope reveal that distant galaxies and their central black holes formed shortly after the Big Bang. An innovation about the speed of light explains how supermassive black holes could have formed primordially. Predictions of Hawking radiation include the possibility of black holes contributing to the energy of stars such as the Sun. Black holes have also been suggested as a source of radiation and magnetic fields in giant planets. Observations of Enceladus raise the possibility that this moon and other objects near Saturn’s Rings contain small singularities. Extrapolations of this methodology indicate that black holes could exist within solar system bodies including planets. Extended discussion describes how their presence could explain mysteries of internal heat, planetary magnetic fields, and processes of solar system formation.

英国高中地理教材栏目设置的特点及启示——以Geography B Evolving Planet为例

以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问题思考类栏目指向不同教学目标,技能训练类栏目凸显实用性和应用性的学科特色,信息提示类栏目关注学生心理特点,考试导向类栏目提高应试答题技巧。受此启发,未来我国中学地理教材栏目设置应有所侧重,即教材栏目在内容设置上要注重针对性,在形式设置上要增加多样性,在外观设置上要注重醒目性。

Relation between Mass and Radius of Exoplanets Distinguished by their Density

The formation of the solar system has been studied since the 18th century and received a boost in 1995 with the discovery of the first exoplanet,51 Pegasi b.The investigations increased the number of confirmed planets to about5400 to date.The possible internal structure and composition of these planets can be inferred from the relationship between planet mass and radius,M-R.We have analyzed the M-R relation of a selected sample of iron-rock and ice-gas planets using a fractal approach to their densities.The application of fractal theory is particularly useful to define the physical meaning of the proportionality constant and the exponent in an empirical M-R power law in exoplanets,but this does not necessarily mean that they have an internal fractal structure.The M-R relations based on this sample are M=(1.46±0.08)R^(2.6±0.2)for the rocky population(3.6≤ρ≤14.3 g cm^(-3)),with 1.5≤M≤39M_(⊕),and M=(0.27±0.04)R^(2.7±0.2)for ice-gas planets(0.3≤ρ≤2.1 g cm^(-3))with 5.1≤M≤639 M_(⊕)(or■2 M_(J))and orbital periods greater than 10 days.Both M-R relations have in their density range a great predictive power for the determination of the mass of exoplanets and even for the largest icy moons of the solar system.The average fractal dimension of these planets is D=2.6±0.1,indicating that these objects likely have a similar degree of heterogeneity in their densities and a nearly similar composition in each sample.The M-R diagram shows a"gap"between ice-gas and iron-rock planets.This gap is a direct consequence of the density range of these two samples.We empirically propose an upper mass limit of about 100 M_(⊕),so that an M-R relation for ice-gas planets in a narrow density range is defined by M∝R^(3).

A Linear Operator Method to Compute the Normal Modes with Rotation of any Asymmetric 3D Planet with Pure Vector Spherical Harmonics

In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surface spherical harmonics(GSSHs) are usually applied to the elliptical models with a stress tensor, which cannot be expressed in vector spherical harmonics explicitly. However, GSSHs involve complicated math. LOM is an alternative to GSSHs,whereas it only deals with the coupling fields of the same azimuthal order m, as is the case when a planet model is axially symmetric and rotates about that symmetry axis. We extend LOM to any asymmetric 3D model. The lower degree spheroidal modes of the Earth are computed to validate our method, and the results agree very well with what is observed. We also compute the normal modes of a two-layer Saturn model as a simple application.

Hubble WFC3 Spectroscopy of the Terrestrial Planets L 98–59c and d:No Evidence for a Clear Hydrogen Dominated Primary Atmosphere

The nearby bright M-dwarf star L 98–59 has three terrestrial-sized planets.One challenge remaining in characterizing atmospheres around such planets is that it is not known a priori whether they possess any atmospheres.Here we report on study of the atmospheres of L 98–59 c and L 98–59 d using near-infrared spectral data from the G141 grism of Hubble Space Telescope(HST)/Wide Field Camera 3.We can reject the hypothesis of a clear atmosphere dominated by hydrogen and helium at a confidence level of ~3σ for both planets.Thus they could have a primary hydrogen-dominated atmosphere with an opaque cloud layer,or could have lost their primary hydrogen-dominated atmosphere and re-established a secondary thin atmosphere,or have no atmosphere at all.We cannot distinguish between these scenarios for the two planets using the current HST data.Future observations with the James Webb Space Telescope would be capable of confirming the existence of atmospheres around L 98–59 c and d and determining their compositions.

Guarding Our Blue Planet

Chinese young people are gearing up for preserving the ocean and marine wildlife.IU Qian is a diving instructor and an ardent volunteer for marine environmental protection.He has been to many tourist attractions around the world,such as the Nile River in Africa and the Red Sea lying between Africa and Asia.He turned his passion into a career,devoting himself to exploring deeper waters and sharing his knowledge and skills with more people in preserving the blue planet.

The Perihelion Precession of the Planets Indicates a Variability of the Gravitational Constant

The gravitational constant G according to the theory of NEWTON is the most imprecise constant of all physical constants. Moreover, there are a number of phenomena which suggest that this is caused by its invariant nature and the gravitation constant might be in fact a variable. In this article, a possible dependence of the gravitational constant on the distance between the two mass points is determined from the observed values of the perihelion displacement of the planets. However, to fit the observed measurements the 1/r2 dependence is modified to a 1/r2+1/R dependence with “R” as the Rydberg constant. With the proposed new power function, the perihelion precessions of the planets are recalculated and then compared with previous observations as well as the postulated anomaly of Saturn.

A Novel Explanation of the Origin of the Magnetic Field of Stars and Planets

Today, the origin of the magnetic field of stars and planets is explained by the dynamo effect. Since Cowling’s anti-dynamo theorem has forbidden a purely axisymmetric dynamo, scientists are all convinced today that the fluid flow in the core of a star cannot be laminar, so it is turbulent. However, we will see in this study that the configuration in which the conductive fluid contained in the core of a star is in rapid rotation around an axis of symmetry is the one that best explains the origin of the magnetic field of stars and planets. It also explains why certain types of stars have very intense magnetic fields. Indeed, we will show here that the magnetic field of stars and planets is created by the electric current generated by the rotational movement of charged fluid particles as in an electromagnet. The lines of this magnetic field are channelled by the solid paramagnetic seed which plays the role of magnetic core in the cores of planets and stars. The seed is composed mainly of Iron and Nickel on the planets and of solid helium-3 in the stars. In this work, we will use this model of rapidly rotating fluids to introduce a new way to ionize a neutral gas and maintain it in a plasma state for indefinitely large time scales, to present a new technique for generating very intense magnetic fields, to establish a new magnetic nucleation process and to propose a new type of nuclear fusion reactor in which the plasma is perpetually rapidly rotating.

基于One Planet Living框架的城市可持续发展规划——以新加坡滨海湾为例

文章基于One Planet Living框架归纳分析了新加坡滨海湾在可持续发展方面实行的具体策略及措施,并重点对交通与出行、水资源可持续管理和健康与福祉三项原则详细研究,总结了滨海湾可持续发展规划的成功经验,以期为我国城市可持续发展提供借鉴和新思路。

Proliferating Satellite Constellations Pose Astronomical and Environmental Challenges

On 6 October 2023,Amazon(Seattle,WA,USA)launched two prototype satellites into low-Earth orbit[1],the inaugural orbiters of Project Kuiper,a constellation of 3236 satellites that will work together to eventually deliver internet to tens of millions of customers worldwide.While Kuiper,named for the belt of ice,rock,and dwarf planets beyond Neptune,is smaller in number than the so-called mega-constellations built by SpaceX(Hawthorne,CA,USA),OneWeb(London,UK),and others,Amazon plans to loft its Kuiper satellites into orbit at a historic pace over the next few years.

A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques

As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is proposed.However, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission.

Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model

Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally intensive.This paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate inversion.The PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore CPUs.The PDE algorithm accurately derives period and pole values from simulated data.The analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole orientations.The PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data analysis.This work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.

Photometric Analysis for Asteroid(81)Terpsichore using Convex Inversion and Phase Function Fitting Methods

The shapes and rotation states(periods and pole orientations)of main-belt asteroids are important for understanding their formation and evolution.In order to obtain sufficient photometric data covering different apparitions for asteroid(81)Terpsichore,ground-based photometric observations in 2020 and 2021 were carried out.By combining published and newly obtained photometric data,we calculated the shape and spin parameters for(81)Terpsichore using the convex inversion method.With this method,we have derived a best fitted pole orientation—(22.2±_(3.1)^(3.3°),17.5±_(5.5)^(10.8°))with a spin period of 10.94±_(0.01)^(0.01)h.Based on the derived convex shape of(81)Terpsichore,we have fitted the H,G+1,G_(2)phase function using the calibrated TESS data and Gaia data after accounting for the lightcurve amplitude correction.As a result,we have derived its absolute magnitude H=8.68±_(0.19)^(0.22)mag with corresponding phase function parameters G_(1)=0.82±_(0.10)^(0.09)and G_(2)=0.02±_(0.02)^(0.03).

Simulating the Escaping Atmosphere of GJ 436 b with Two-fluid Magnetohydrodynamic Models

Observations of transmission spectra reveal that hot Jupiters and Neptunes are likely to possess escaping atmospheres driven by stellar radiation.Numerous models predict that magnetic fields may exert significant influences on the atmospheres of hot planets.Generally,the escaping atmospheres are not entirely ionized,and magnetic fields only directly affect the escape of ionized components within them.Considering the chemical reactions between ionized components and neutral atoms,as well as collision processes,magnetic fields indirectly impact the escape of neutral atoms,thereby influencing the detection signals of planetary atmospheres in transmission spectra.In order to simulate this process,we developed a magnetohydrodynamic multi-fluid model based on MHD code PLUTO.As an initial exploration,we investigated the impact of magnetic fields on the decoupling of H^(+)and H in the escaping atmosphere of the hot Neptune GJ436b.Due to the strong resonant interactions between H and H^(+),the coupling between them is tight even if the magnetic field is strong.Of course,alternatively,our work also suggests that merging H and H^(+)into a single flow can be a reasonable assumption in MHD simulations of escaping atmospheres.However,our simulation results indicate that under the influence of magnetic fields,there are noticeable regional differences in the decoupling of H^(+)and H.With the increase of magnetic field strength,the degree of decoupling also increases.For heavier particles such as O,the decoupling between O and H^(+)is more pronounced.Our findings provide important insights for future studies on the decoupling processes of heavy atoms in the escaping atmospheres of hot Jupiters and hot Neptunes under the influence of magnetic fields.

Artificial intelligence and evidence-based research will promote the development of traditional medicine

Traditional medicine(TM)has progressively achieved international recognition.The recent first-ever World Health Organization(WHO)Traditional Medicine Global Summit 2023 has undoubtedly highlighted the significance of TM^([1]).This conference was held in India during August 17–18,2023^([2]),aiming to mobilize political commitment and evidence-based action supporting TM and integrating it to advance the health and well-being of the people and planet.

基于高分辨率卫星影像的土壤生态遥感监测

土壤作为陆地圈中的重要组成部分以及绝大多数动植物生存的基础,在生态环境循环中扮演着重要的角色。本研究通过地面实测数据联合卫星影像的手段,开展了土壤元素含量遥感反演,分别计算土壤温度、土壤相对含水量、土壤有机质含量。本研究首先采用背携式ASD地物光谱仪对土壤进行光谱实测,并取样化验,得到点状土壤元素含量,通过构建多指数类型模型与最优模型选择,进行基于卫星影像的土壤生态遥感反演,以此探讨土壤生态遥感监测的适用性。通过本研究的开展,得到的基于高分辨率卫星影像的土壤生态遥感监测结果与实际情况相符,土壤温度、土壤相对含水量、土壤有机质含量均在合理范围之内;通过实测数据精度验证可知,整体反演精度较高,各个点位反演数值与实测数值高度吻合,数值相差较小,为后期相关研究的开展提供了参考。

ISO Annual Meeting

The ISO Annual Meeting is the world’s premier event for the international standards community.This year’s event is hosted by ICONTEC,the national standards body of Colombia.With the theme“Breaking boundaries”,this open-to-all event comes at a pivotal time for the world.Over the course of a week,participants will engage in meaningful discussions about the most pressing challenges facing our planet today,while also exploring collaborative standards-based solutions for the future.

PLANET在GSM移动通信网频率优化中的应用

介绍了北电网络系统中通常使用的软件规划工具PLANET在GSM移动通信网频率规划中的操作特点.在网络规划后期的优化阶段,对典型的三扇区基站标频的分配工作中,利用剩余频点的优先级排序法,可有效地抑制同、邻频干扰的发生.